I wonder who fund the development of building of our Churches? I mean who built them? Is it Holy See?

Like we know today, there are some big, great and beautiful cathedrals in most city in the world, and the ordinary churches usually are big too. Not yet to mention the St.Peter Basilica at Vatican, Rome.

I'm thinking there are many great and big Catholic Churches in the world, our Catholic assets must be quite an enormous sum of money.

Who built those churches? From where they got its fund?

Oh, And what is the difference between basilica, cathedral, and ordinary church? Are they categorized based on how big they are?